Erroneous Perceptions in Generating Sequences of Random Events¹

This paper reports the results of 2 studies that examine the perceptions of individuals attempting to generate random sequences. It was hypothesized that erroneous perceptions dominate probability judgment. The first study demonstrated that subjects verbalized significantly more erroneous than accurate perceptions when generating sequences of random binary events. The second study was designed both to replicate these data and to assess the role of motivation on the frequency of misconceptions. Results showed that the total number of erroneous perceptions again outnumbered accurate perceptions but, motivation did not increase the number of misconceptions. A basic error concerned subjects' inability to consider events as being independent of each other. The theoretical and practical implications of these results are discussed in relation to the psychology of gambling.